Interest arbitration is a process whereby the issues not resolved in contract negotiations between the employer and the union may be presented to an impartial arbitrator for resolution. Washington State Ferries employees, home care individual providers, and commissioned officers of the Washington State Patrol have access to interest arbitration. Washington State correctional employees gained interest arbitration rights for the term of their current collective bargaining agreement when Governor Inslee agreed to a Memorandum of Understanding (MOU) that was originally signed in 2013 and extended two years later.

Typically, interest arbitration is provided to employees who engage in essential services, such as public safety, and who therefore do not have the right to strike.